title: Influence of dietary calcium concentration on body size and bone composition in rats during recovery from malnutrition.
abstract: OBJECTIVE
  The purpose of our study was to assess the influence of different levels of calcium (Ca) in a diet containing 30% protein on the rehabilitated of the body size from protein-energy malnutrition (PEM) and to establish the optimal Ca/protein ratio for attaining a normal body composition.
  
  
  METHODS
  Weanling female Wistar rats were fed with protein-free diet up to a weight deficit of 20 +/- 1%. Then they were arranged in groups (TO) and fed diets with 30% protein and 0.0, 0.2, 0.4, 0.6, 0.9 or 1.2% Ca for 28 days (T28). Food and deionized water were given ad libitum. Body weight and length were recorded every 3 days. At T28, the animals were sacrificed to determine femur composition.
  
  
  RESULTS
  At T13, weight-for-age (W/A) was within the normal range for rats consuming > or = 0.6% Ca. At T28 all groups showed adequate W/A. Although length-for-age was adequate during rehabilitated period, rate of weight gain improved when Ca was > or = 0.6%. Femur length did not show significant difference between groups. Total femur Ca content and mg Ca/g of dry-weight tissue increased with increments in dietary Ca concentration and tended to plateau with 0.4% Ca. Ca/P ratio reached the highest value with 0.9% Ca.
  
  
  CONCLUSIONS
  Our findings indicate that at a dietary protein level of 30% the Ca/protein ratio is a limiting factor in attaining of normal body size; this is achievable when Ca concentration is 1.2% and the Ca/protein ratio is 0.04.
authors.affiliation: Department of Biochemistry, University of Buenos Aires, Argentina.
authors.forename: P N
authors.initials: PN
authors.lastname: Rodriguez
authors.forename: S M
authors.initials: SM
authors.lastname: Friedman
authors.forename: P
authors.initials: P
authors.lastname: Boyer
authors.forename: M L
authors.initials: ML
authors.lastname: de Portela
mesh_terms: D000375:Aging; D000818:Animals; D001823:Body Composition; D001824:Body Constitution; D001835:Body Weight; D002118:Calcium / Q000032:analysis; D002136:Calcium, Dietary / Q000008:administration & dosage*; D004044:Dietary Proteins / Q000008:administration & dosage; D005260:Female; D005269:Femur / Q000033:anatomy & histology / Q000737:chemistry; D011502:Protein-Energy Malnutrition / Q000534:rehabilitation*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D002136:Calcium, Dietary; D004044:Dietary Proteins; D002118:Calcium